What is blowdown cooling tower?
What is blowdown cooling tower?
Cooling tower bleed-off/blowdown is the flushing of a portion of high mineral concentration cooling tower system water down the drain, while simultaneously replacing it with fresh water. This process dilutes the system water mineral concentrations that steadily increase due to water evaporation.
Why do cooling towers have a blowdown valve?
Blowdown is used to help avoid the over cycling of dissolved solids that would lead to deposition in your cooling system. Wasted Water – Too much blowdown forces the tower makeup water valve to open and add water to maintain the sump level.
Is cooling tower blowdown continuous?
Cooling towers, closed circuit coolers and evaporative condensers require continuous blow down or “bleed off” with added make-up water to maintain an acceptable concentration level.
What is the purpose of blowdown?
The primary purpose of blowdown is to maintain the solids content of boiler water within certain limits. This may be required for specific reasons, such as contamination of the boiler water. In this case, a high blowdown rate is required to eliminate the contaminants as rapidly as possible.
How do you calculate blowdown in a cooling tower?
It is calculated by this equation:
- Evaporation loss = 0.00085 Wc (T1-T2)
- Drift loss = 0.02% water supply [for new development in eliminator design]
- Blowdown = [ Evaporative loss – (COC – 1) x Drift loss] /(COC – 1)
Why are cooling towers Hyperbolic?
Hyperboloid (sometimes incorrectly known as hyperbolic) cooling towers have become the design standard for all natural-draft cooling towers because of their structural strength and minimum usage of material. The hyperboloid shape also aids in accelerating the upward convective air flow, improving cooling efficiency.
What bleed cooling tower?
Cooling tower bleed-off/blowdown occurs periodically throughout the day to remove high concentrations of mineralized water from the tower due to evaporation. Scale formation occurs if the concentration of minerals in a cooling tower increases to a level higher than the saturation point of the system water.
How do cooling towers reduce water loss?
There are frequently three ways to reduce water consumption in a cooling tower: 1) Changing wet cooling tower to hybrid or dry cooling tower, 2) Reduction in blowdown with increasing of concentration cycles and 3) Using air to air heat exchanger on the cooling tower.
What is the difference between blowdown and depressurization?
is that blowdown is (chemical engineering) the removal of liquid and solid hydrocarbons from a refinery vessel by the use of pressure while depressurization is the act, or an instance, of depressurizing; a reduction of atmospheric pressure within a chamber or space vehicle etc.
Which cooling tower is more efficient, wet or drying cooling?
Wet cooling towers work efficiently in hot and dry climates, but as the ambient air becomes humid, the performance of wet cooling towers fall. Conversely, dry cooler performance is not affected by air humidity but relies on the air temperature.
Are cooling towers bad?
According to Centers for Disease Control and Prevention (CDC), cooling towers can be a breeding ground for Legionella bacteria , the microbes that cause Legionnaires’ disease. Here’s why: Bacteria thrive in warm, wet conditions, making cooling towers an ideal environment .
What chemicals are in cooling tower?
Chemicals used in cooling tower water treatment are: Bicarbonate as known as Hydrogen Carbonate is a chemical compound with HCO3- formula. We can usually find bicarbonate commonly in sodium bicarbonate form, which is in baking soda. In cooling water tower system, bicarbonate used for corrosion inhibitors.
What happens in cooling tower?
A cooling tower is a heat rejection device that rejects waste heat to the atmosphere through the cooling of a water stream to a lower temperature.
